The Turkish election board has declared incumbent Recep Tayyip Erdogan the outright winner of the country's pivotal presidential election, avoiding the need for a runoff and providing him with sweeping new powers as president.

Erdogan defeated his nearest rival with an “absolute majority of all valid votes," Sadi Guven, the head of the Supreme Election Committee (YSK), told reporters in Ankara early on June 25, without giving exact numbers.

The YSK is expected to publish full, final results later on June 25.

Earlier, state television said that with 99 percent of the votes counted, Erdogan had 52.5 percent of the tally, while leading challenger Muharrem Ince had 31 percent.

State media said that in the simultaneous parliamentary contest, the AKP had won 42 percent and its MHP ally had 11 percent, while Ince's main opposition Republican People's Party (CHP) had 23 percent.

The pro-Kurdish Peoples' Democratic Party (HDP) had 11 percent, which would put it above the 10 percent needed to enter parliament.

The opposition nationalist Iyi (Good) party had 10 percent, according to state media.

Turnout was 87 percent for both the presidential and parliamentary contests, officials said.

"The nation has entrusted to me the responsibility of the presidency and the executive duty," the 64-year-old said in televised remarks from Istanbul.

"The message is clear," he also said. "With turnout of nearly 90 percent, Turkey has taught the whole world a democracy lesson."

"I thank all of my citizens, no matter from which party, who went to the ballot box to exercise their democratic right," he added.

Amid signs of a weakening economy, Erdogan in April declared that presidential and parliamentary elections would be held on June 24, 17 months earlier than planned.

Under constitutional amendments approved after a controversial 2017 referendum, Turkey is making a transition from a parliamentary system to a presidential one -- giving the next president considerable power, abolishing the prime minister's post, and eliminating many of the checks and balances designed to help parliament protect against the misuse of presidential powers.

The changes will take effect after the elections.

"Turkey is staging a democratic revolution," Erdogan told reporters in the polling station in Istanbul where he voted earlier in the day. "With the presidential system, Turkey is seriously raising the bar, rising above the level of contemporary civilizations."

After being declared the winner, Erdogan on June 25 said he would act more decisively against terrorist organizations and would liberate more territory in Syria to allow "our guests" to go home safely, referring to the thousands of Syrian refugees who have fled the bloody seven-year civil war in the Middle East country.

Polls had suggested the possibility that the presidential vote could head into a second-round runoff on July 8 and that the AKP could lose its parliamentary majority after 16 years.

Ince had initially questioned the validity of unofficial results released by state media giving Erdogan and his party the clear-cut victories.

However, early on June 25, Ince was quoted by HaberTurk TV as saying, "I admit that Erdogan has won the election."

Ince, the CHP leader, was backed by the newly formed National Alliance, which along with secular social democrats, includes center-right conservatives, nationalist liberal conservatives, and conservative Islamists.

Nation Alliance parliamentary candidates had vowed that if they secure majority control of the legislature, they will try to roll back the Erdogan-backed constitutional amendments narrowly approved in the controversial 2017 referendum.

Erdogan has dominated Turkish politics for more than 15 years, first as prime minister and since 2014 as president. He remains popular with vast segments of the population.

He founded the AKP after the previous Islamic party led by his mentor, Necmettin Erbakan, was banned.

He survived a coup attempt led by a renegade army faction on July 15, 2016, leading to a crackdown on opponents that has been criticized by many in the West.

In Germany, Sevim Dagdelen, chairwoman of the German-Turkish parliamentary group and an ethnic Kurd, told the dpa news agency that the elections were "neither free nor fair."

"Erdogan has reached his goal of an authoritarian presidential system through manipulation that began long before election day," said Dagdelen, a member of Die Linke (The Left) party in Germany, which has a large ethnic-Turk and Kurdish population.

After 80 percent of ballots from Turks eligible to vote in Germany were counted, Erdogan had won 65.7 percent of them, officials said.